Opened 13 years ago

Closed 13 years ago

#2780 closed defect (fixed)

[with patch, positive review] factorisation over number field has wrong unit part

Reported by: dmharvey Owned by: tbd
Priority: major Milestone: sage-3.0
Component: factorization Keywords:
Cc: Merged in:
Authors: Reviewers:
Report Upstream: Work issues:
Branch: Commit:
Dependencies: Stopgaps:

Status badges

Description

When factoring a multivariate polynomial over a number field, the unit part of the factorisation is reported incorrectly:

sage: K.<a> = NumberField(x^2 + 1)
sage: R.<y, z> = PolynomialRing(K)
sage: f = 2*y^2 + 2*z^2
sage: F = f.factor(); F
2 * (y + (-a)*z) * (y + a*z)
sage: F.unit_part()
1

The unit part should be 2.

Reported by Genya Zaytman.

See also: http://groups.google.com/group/sage-devel/browse_thread/thread/cc519fe6a67ff9e

Attachments (1)

2780-factorization_unit.patch (1.7 KB) - added by AlexGhitza 13 years ago.

Download all attachments as: .zip

Change History (5)

comment:1 Changed 13 years ago by mabshoff

  • Component changed from basic arithmetic to factorization
  • Milestone set to sage-3.0
  • Owner changed from somebody to tbd

Changed 13 years ago by AlexGhitza

comment:2 Changed 13 years ago by AlexGhitza

  • Summary changed from factorisation over number field has wrong unit part to [with patch, needs review] factorisation over number field has wrong unit part

See the patch.

comment:3 Changed 13 years ago by mhansen

  • Summary changed from [with patch, needs review] factorisation over number field has wrong unit part to [with patch, positive review] factorisation over number field has wrong unit part

Looks good to me.

comment:4 Changed 13 years ago by mabshoff

  • Resolution set to fixed
  • Status changed from new to closed

Merged in Sage 3.0.alpha4

Note: See TracTickets for help on using tickets.